Finally got round to it. Success! Thanks for your guidance on this. Must admit I had moments of extreme doubt that I was going to get it all back together again but all worked perfectly. Things to look out for as follows:
Getting the electrical connector off the small speaker. What a swine that is, somehow did it in the end, perseverance.
Locating the plastic cap on the rear edge of the door. Once removed a long torx driver to slacken the screw. Once slackened, the smaller part of the outside door handle can be pulled off. With that off the longer part pulls along, revealing the magic screw that is under the long handle section. Without getting to that screw under the long handle section you will not win the battle.
Once the mechanism is out and on the work bench, you cant take too many photos. Thankfully I took plenty because at one point I found a spring on the bench and had no clue where it had come from.
Stripped down only the larger of the two motors, electrical connector cleaner and cotton buds used there. Carefully all reassembled. You will need a small cable tie.
Oh and.. Inside the door there's a covering of thin bubble wrap type material, glued on all round the edge with something like chocolate spread. You only need to remove the rear corner of this stuff and if careful it can be peeled off and replaced as good as new. Not a disaster if it all goes but it doesn't need to.
I took some pics as I went along and have tried to post them but the file size is too large.
